Spotting device



i l l ,i S

-- IWILJL lj I [LJQ @RKK J. W. SIMS SPOTTING DEVICE Filed March 17, 1955 Aug. 2s, 1956 United States Patent 2,760,270 SPTTING DEVICE John W. Sims, Jefferson, Pa.

Application March 17, 1953, Serial No. 342,921

2 Claims. (Cl. 33-46) This invention relates to an improved spotting device which enables an operator to position a traveling appliance, such as a coke pusher machine.

Certain traveling appliances, of which a coke pusher machine is typical, have an operators station offset sideways from mechanisms which must be aligned with various fixed structures. A pusher machine for example travels on tracks alongside a battery of by-product coke ovens. One common type has a glass enclosed operators cab in its central portion facing the row of oven doors, a door extractor mechanism offset to the left of this cab, a pusher ram approximately in line with the cab, and a leveler bar offset to the right. When the charge in an oven is ready for pushing, the extractor mechanism first must be alined and engaged with the door for removing the door. Next the machine must be shifted to the left and the pusher ram aligned with the door opening for pushing the coke out t.e other side. Thereafter the Inachine must be shifted back to the right and the extractor mechanism again aligned with the opening to replace the door. Later, after the oven has been recharged with coal, the leveler bar must be aligned with a small door adjacent the top of the oven and inserted to level the charge. These various mechanisms must be aligned quite accuratel for example, the extractor mechanism commonly must be aligned with the door opening to an accuracy within a half inch or less to replace a self-sealing door.

An object of the present invention is to provide an improved spotting device which enables an operator to position a traveling appliance such as a pusher machine easily and accurately in any desired 'aligned relation with a minimum ofjogging back and forth.

A further object is to provide an improved spotting device which does not rely on mechanical indicators, but instead relies on a readily visible optical reilection that can be accurately located with respect to a fixed structure.

ln accomplishing these and other objects of the invention, l have provided improved details of structure, a preferred form of which is shown in the accompanying drawing, in which the single figure is a somewhat schematic horizontal sectional View of a portion of a battery of col-:e ovens and a pusher machine equipped with a spotting device constructed in accordance with my invention.

The drawing shows a number of by-product coke ovens 1Q. 12, 13, 14 and 15 of a single battery, which commonly consists of sixty or more ovens in all. Flue chambers 16 are located intermediate the ovens, and vertical buckstays 17 support the Wall outside said chambers. The pusher side of each oven has a fixed door frame 18 and a door 19 removably mounted in said frame. The ovens are all alike so that corresponding points on successive ovens are uniformly spaced. A self-propelled pusher machine 20 runs on a track 21 along the pusher side of the battery and includes 'an operators cab 22, a door extractor mechanism 23, a pusher ram 24 and a leveler bar 25. The cab has a vertical glass front or windshield 26 spaced a distance x from the outer edges of the dor frames 18, all of which frame edges are in a common vertical plane. In practice the distance x can be about 10 feet. The structure thus far described is conventional in coke ovens, and therefore is not described nor shown in greater detail. This structure affords a typical environment for the spotting device of my invention, but is not to be construed as limiting, since it is apparent that the device could be used in other appliances where similar problems exist.

It is seen that the extractor mechanism 23 is oifset from the cab 22 on one side and the leveler bar 25 offset on the other side, while the ram 24 is approximately in line therewith. The operators usual position in the cab is indicated at A. From this position he must view any oven with which the extractor mechanism or the leveler bar is aligned along an oblique line of vision. Thus it is diilcult for him to align the extractor mechanism or the leveler bar with an oven with the necessary precision. Pusher machines commonly weigh 100 tons or more so that jogging them back 'and forth to align them is undesirable. It has been customary to equip pusher machines with mechanical pointers to assist in aligning them, but such pointers get distorted and also are difficult for the operator to see; consequently they have not been satisfactory for the purpose.

In accordance with the present invention, the back portion of the operators cab 22 contains a fixed light source 27 located a distance y behind the windshield 26. This distance should be at least 'as great as the distance x between the windshield and the outer edges of the door frames :and in practice likewise can be about 10 feet. The light source 27 is focused to cast a concentrated sharply defined light beam, such as a cross or a dot, and preferably colored, in a direction normal to the windshield 26. An image of this light is reflected back by the glass of the windshield, which appears to act as a mirror. In accordance with Well known principles of optics, this reflected image appears to be the same distance y beyond the windshield as the distance y between the light source 27 and the windshield. If the distance x and y are equal, the image appears to be located in the same plane as the outer edges of the door frames 18. The distance v is sui'liciently large that the reflected image does not appear to move appreciably as the operator views it from different positions in the cab.

The light source 27 is mounted rigidly in a fixed position in the cab so that its reflected image is always in the same position relative to the door extractor mechanism 23, the pusher ram 24, and the leveler bar 25, and thus provides a xed point to serve las a spotting source for the operations to be performed by these devices. The light source 27 is offset sideways from the operators position A and it is located where its reflected image appears to be exactly on one of the frames 1S whenever the extractor mechanism, pusher ram or leveler bar is properly aligned with an oven. For example, when the operator wishes to align the extractor mechanism 23 with the door 19 of oven 10, he can bring the pusher machine 20 to a position where the reflected image appears to be on the outer edge of the door frame 18 of oven 14, which is the third oven to the right of oven 10. When he wishes to align the pusher ram 24 with the door opening of oven 10 after he has removed the door, he can shift the pusher machine to a position where the reilected image appears to be on the outer edge of the door frame of oven 12, which is the first oven to the right of oven 10. When he Wishes to insert the leveler bar 25 in oven 13, he can shift the pusher machine to a position where the reected image appears to be on the outer edge of the door frame of oven 10 which is the second to the left of oven 13. By experience the operator can tell the exact spot on the frame on which the image should appear for each diierent operation, and this spot is the same for all the ovens except those at ythe end of the battery. For these end ovens targetv points can be painted orv otherwise marked on the battery. It is also apparent that target points may be 'marked' on the oven structure, if desired, alternatively to using unmarked points in this structure.

From the foregoing description it is seen that the present invention affords a simple and reliable spotting device for aligning a traveling appliance with a fixed structure. The optical image reectcd by mirror action of the glass windshield isV always visible to the operator irrespective of bright lights or other adverse` visibility conditions. The reflected image furnishes a clear-cut, well dened spot that can be located accurately on the guide marker. Since the spot is :a reflected image, it is invisible to an observer on the outside.

While I have shown and described only a single embodiment of the invention, it is apparent that modications may arise. Therefore, I do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

I claim:

l. Means for spotting a movable structure with respect to a stationary structurev comprising a transparent and reliecting window mounted on the movable structure in a plane parallel to the stationary structure, a target mounted on the stationary structure and spaced from said window, and a light source mounted on the movable structure and located on the opposite side of said window from said target and spaced from the window yby at least as great a distance as the spacing between said window and said target, said light source being focused to cast a sharply defined light beam toward said Window in a direction normal thereto and thus to furnish a reflected image therein, said image appearing to be located a distance beyond said window equivalent to the spacing between said light source an`d said window and thus being capable of alignment with said target.

2. In an assembly which includes a fixed structure, a traveling appliance adaptedv to move alongside said structure, and elements on said structure and said appliance which require selective alignment, the improvement which comprises means' providing a surface which both reects and transmits light Xed t0 said appliance and movable in a plane parallel with said structure, a target iixed to said structure spaced from said surface, and a light source tixedtto-said appliance on the opposite side of said surface from said target and spaced from said surface at least as far as said target is spaced therefrom, said source being adapted to cast a sharply defined light beam in a direction normal to said surface and thus to produce a reflected image in said surface for spotting on said target.

References Cited in the le of this patent UNITED STATES PATENTS 1,229,225 Carpenter et al. June l2, 1917 2,416,071 Shonnard Feb. 1S, 1947 2,580,240 Newman Dec. 25, 1951 

